Integrate JWT Authentication from the Opencast PHP Library

[ferishili]

This issue focuses on implementing and configuring JWT (JSON Web Token) authentication using the Opencast PHP Library.
The goal is to ensure secure and seamless communication between this plugin and Opencast by leveraging the library's built-in JWT authentication capabilities.

Tasks:

• Integrate JWT-based auth into our existing authentication flow.
• Identify places in which JWT auth is required.
• Document the setup and configuration process.
• Opencast-JWT-iFrame with refresh token capability

Expected Outcome:
A working JWT authentication system that securely authenticates API requests to Opencast using the PHP library.

Ref issue:
elan-ev/opencast-php-library#50